The present invention relates to the fields of passive exercise and pulmonary therapy and, more specifically, to a method and apparatus for preventing, treating or improving the efficacy of a variety of conditions and treatments including breathing difficulties, pitting peripheral edema, post-surgical adhesions, efficacy of CPAP/BiPAP and/or the delivery of inhaled medications.
Shortness of breath and general breathing difficulties can be indicative of a variety of diseases and conditions suffered by individuals throughout the world including asthma, sleep apnea, emphysema, bronchitis, pneumonia, and chronic obstructive pulmonary disease (COPD). Breathing difficulties and breathing obstruction have also been linked to an increased risk of sudden infant death syndrome (SIDS).
Sleep apnea is a sleep disorder that includes abnormal pauses (e.g., a few seconds or minutes) in breathing or instances of abnormally low breathing. These pauses, or apneas, may occur between five and thirty times or more an hour. An abnormally low breathing event is called a hypopnea. Sleep apnea occurs in patients in one of three forms: central sleep apnea, obstructive sleep apnea, and complex or mixed sleep apnea. Individuals suffering from sleep apnea are typically unaware of their condition and experience daytime fatigue and sleepiness.
A variety of treatments have been developed for the treatment of sleep apnea. These treatments range from simply sleeping on one's side and avoiding alcohol or sleeping pills, jaw-shifting mouthpieces, and even surgery. One of the safest, most effective, and commonly prescribed treatments is the use of a continuous positive airway pressure (CPAP) device. A CPAP device includes a facial mask connected via a tube to a bedside machine. The machine generates air pressure to keep the patient's airways open during sleep. Typically, a sleep study is conducted by a medical professional or therapist to determine the appropriate settings for the CPAP machine. The patient is then given a prescription containing these settings. Although the CPAP device is safe and effective, many patients find it extremely uncomfortable and refuse to use the CPAP device.
As noted (above), COPD is another condition associated with shortness of breath and general breathing difficulties. There are two main forms of COPD, namely chronic bronchitis and chronic emphysema; however, most individuals with COPD have a combination of both forms. COPD is characterized by obstruction to airflow and typically is not fully reversible. The primary symptoms of the disease are a chronic cough, shortness of breath, chest tightness, increased mucus production, and frequent clearing of the throat. It is now the third leading cause of death in the United States accounting for approximately 4% of all deaths in the United States. Further, it is one of the fastest growing causes of death, second only to the AIDS virus. Death rates from COPD in recent decades increased more than 60%, whereas death rates for coronary heart disease, the current leading cause of death in the United States, decreased 30%. More than 12 million people in the US live with the diagnosis of COPD.
COPD typically develops slowly. Symptoms often worsen over time and can limit the ability to do routine activities. Severe COPD may prevent basic activities like walking, cooking, or self-care. Chronic obstructive pulmonary disease has become one of the most prevalent chronic diseases in America today. Over the next 20 years, medical costs related to COPD are expected to total approximately $832.9 billion in the United States.
A variety of treatments for COPD and other diseases and conditions associated with shortness of breath and breathing difficulties have been proposed. For example, medications such as bronchodilators and steroids have proven to be effective treatments. Bronchodilators widen the air passages of the lungs by relaxing bronchial smooth muscle, while steroids can reduce lung inflammation. For some patients, however, these medications alone are insufficient.
Oxygen therapy has also proven to be effective at reducing a patient's sensation of air hunger (dyspnea), and the declining cost and increasing mobility of oxygen-therapy systems has increased the popularity of this treatment. Nevertheless, oxygen therapy does not reduce the level of carbon dioxide in a patient's bloodstream because the volume of air exhaled by the patient is not increased. Thus, oxygen therapy alone is insufficient to treat all of the physiological effects of shortness of breath.
Cardiopulmonary rehabilitation programs have been used to treat diseases and conditions associated with shortness of breath. These programs typically include active exercise (e.g., walking on a treadmill) to increase lung function. Some patients, however, are simply incapable of active exercise because the mere act of breathing requires so much energy that physical exertion would jeopardize their ability to breath. Thus, active exercise may only be beneficial to some patients.
Accordingly, passive exercise treatments have been developed that stimulate deeper breathing but do not require physical exertion. One such treatment is positive pressure ventilation (PPV), which involves forcing air into the lungs, thereby increasing pressure in the airways relative the outside. U.S. Pat. No. 7,556,038 discloses a method of monitoring and controlling a patient's breathing rate using a PPV device. PPV has been used to treat shortness of breath and breathing difficulties, particularly during severe exacerbations and end-stage COPD. There are risks associated with PPV, however, and those risks increase as the pressure required to inflate the patient's lungs increases.
Another form of passive exercise treatment involves facilitating a patient's natural breathing by physically moving the patient's body. Typically, these passive exercise treatments involve placing the patient on a bed-like device that moves in a particular manner to facilitate breathing or encourage the movement of fluids within the patient, or both. For example, some passive exercise beds rock a patient from side-to-side in an oscillating motion. Other passive exercise beds “slide” the patient forward and backward, i.e., in the direction of the patient's feet and then in the direction of the patient's head.
Passive exercise has also proven to be beneficial to hospital patients confined to their beds due to recent surgery or immobility, as well as bed-ridden residents of nursing homes. For example, passive exercise can reduce the occurrence, frequency, or severity of bedsores. U.S. Pat. No. 4,999,861, which is hereby incorporated by reference in its entirety, discloses a bed constructed of independently movable segments that can be reciprocated down the length of a patient's body to passively exercise the patient and relieve the constant pressure that causes bedsores. Additionally, passive exercise may reduce the occurrence of blood clots by preventing blood from pooling in an immobile patient's legs or other areas of a patient's body. Furthermore, passive exercise can relieve or prevent adhesions that can occur after surgical procedures. Adhesions are bands of scar-like tissue that form between two surfaces in the body and can occur throughout the body. Passive exercise can be particularly effective at preventing abdominal adhesions.
Edema is excess fluid that is trapped in the body's tissues, and presents itself as swelling, often in the hands, arms, ankles, legs and feet. This condition is typically linked to problems with the venous or lymphatic system. This condition can be especially problematic when lymphostatic edema develops, which is the abnormal accumulation of protein in the lymph vessels, along with osmotically held fluids in the interstitial space. As toxins accumulate, cells are unable to function properly, thereby resulting in various metabolic and infectious problems. Passive exercise can be effective at preventing and treating edema.
Certain treatments for breathing conditions paradoxically rely on breathing function to be efficacious, for example Continuous Positive Air Pressure (CPAP), Bilevel Positive Air Pressure (BiPAP), Metered Dose Inhaler (MDI), Dry Powder Inhaler (DPI), and nebulizers. Passive exercise can be effective at improving peak breathing flow, and therefore facilitating improved medication delivery.
U.S. Pat. No. 6,817,363 discloses a variety of passive exercise treatments. One treatment includes tilting a patient from left to right about a fixed longitudinal axis extending parallel to an axis extending from the patient's head to the patient's feet. Another treatment includes rotating, or pivoting, the patient's body around a fixed axis that is perpendicular to the patient's height and is located near the patient's torso (i.e., a see-saw type motion). The pivoting motion raises the patient's head while lowering the patient's feet, and then lower's the patient's head while raising the patient's feet. The treatment methods and devices disclosed in U.S. Pat. No. 6,817,363 involve rotating the patient's body around a fixed pivot axis, which generates a sensation of rapid acceleration at the points of reversal. These sudden accelerations can cause significant patient discomfort, including nausea, particularly when the passive exercise treatment is performed for longer periods of time.
U.S. Patent Application Publication No. 2010/0063427 discloses a therapeutic system that includes an oscillatory, pivoting table for applying motion-induced therapeutic sensory stimuli to a user. The disclosed table, however, rotates the user's body around a fixed pivot axis and, therefore, also generates rapid accelerations and the associated discomfort.
Therefore, a need exists for a passive exercise method and device for the treatment of individuals suffering from breathing difficulties that reduces or eliminates sensations of rapid acceleration and provides a more comfortable treatment experience.